Texel

In 3D graphics, a texel (short for "texture pixel") is an individual element of a texture. A texture consists of a grid of texels, much as a raster image consists of a grid of pixels. Textures are rendered onto 3D surfaces to convey qualities such as color, depth, and reflectivity. Multiple textures may be layered to create complex surface overlays.

Texture mapping associates points on a model's surface with positions in a texture, commonly through texture coordinates (a.k.a. UV coordinates) assigned to polygon vertices. During rendering, these coordinates are interpolated across the polygon and used to sample the texture. A fragment's sampling location may fall between texel centers, or its footprint in texture space may cover multiple texels. Texture filtering determines how texel values are selected or combined during texture magnification or minification.

In programmable graphics APIs such as WebGL, texture sampling and lighting calculations are controlled by shaders and may be performed together in the same shader.